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T Wahlberg

Publications and source records attributed to T Wahlberg.

14 recordsLinked to original sources
PubMed1994

Low-molecular-weight heparin (Fragmin) versus heparin for anticoagulation during cardiopulmonary bypass in open heart surgery, using a pig model.

Fragmin and heparin were studied in pigs during 120 min of cardiopulmonary bypass (CPB) and up to 240 min postoperatively, with respect to clotting, bleeding and the effects of protamine. Thirty-three pigs received bolus injections of 300 IU/kg with or without additional dosage during CPB and with or without subsequent protamine sulphate. Doses of Fragmin 60% higher were necessary to prevent clotting. These had 100% higher anti-FXa levels but about 50% shorter activated coagulation time (ACT) compared with heparin. Anti-FXa increased with cumulative doses of heparin and Fragmin but ACT and activated partial thromboplastin time (aPTT) did not, indicating a larger loss of thrombin inhibition compared with anti-FXa in both drugs during CPB. Thrombin inhibition was crucial for prevention of clotting. Protamine efficiently normalized ACT in the Fragmin group but left a residual 20% anti-FXa, which did not increase the bleeding tendency. Fragmin could adequately be monitored with ACT and would be a safe alternative to heparin in CPB.

Animals↗
PubMed1994

Fragmin (LMWH) vs heparin for anticoagulation during in vitro recycling of human blood in cardiopulmonary bypass circuits: dose-dependence and mechanisms of clotting.

Low-molecular-weight heparin (LMWH) (Fragmin) vs heparin was studied in vitro in order to investigate its antithrombotic efficacy in the isolated thrombogenic link of cardiopulmonary bypass (CPB). Fresh human blood (400 ml) with various dosages of the anticoagulant was recycled in a CPB circuit for 120 min. The standard dosage of heparin (1,500 IU, n = 6) was compared with a lower dosage (1,000 IU, n = 3) and several dosages of Fragmin (IU anti-FXa): 750 (n = 1), 1,500 (n = 3), 2,100 (n = 4) and 2,500 (n = 3). Clotting occurred in three Fragmin experiments at dosages of 750, 1,500 and 2,100 IU. This was associated with short activated clotting time (ACT) and activated partial thromboplastin time (aPTT) but was independent of the levels of anti-FXa, FVIII, von Willebrand factor and prothrombin complex. It was concluded that at least twice the dose of Fragmin (anti-FXa), compared with heparin, was required, suggesting that thrombin inhibition is crucial for the antithrombotic efficacy of heparin in CPB circuits. Absence of fibrinolytic markers suggests that the well known enhancement of fibrinolysis often seen during CPB, is not due to heparin interaction with normally circulating blood components, but rather to interaction with the vessel walls or to the surgical trauma itself.

Adult↗
PubMed1982

Carriers and noncarriers of haemophilia A: I. Multivariate analysis of pedigree data, screening blood coagulation tests and factor VIII variables.

From a material of 18 obligate carriers of haemophilia A and 40 healthy females, a discriminant function was created, based on ratio of factor VIII related antigen (electroimmunoassay = EIA) to factor VIII activity (one-stage assay), factor VIII related antigen (radioimmunoassay = RIA) and number of bleeding symptoms. The standard deviation of p-values for carrier- and non-carrier state (less than 0.05) was estimated by a procedure built on the 'jack-knife' method. By combined information of pedigree- and discriminant analysis data, 43 possible carriers were classified as carriers/noncarriers with about 95% confidence. Carriers were significantly older, had more bleeding symptoms, longer APTT, lower factor VIII activity, factor VIII procoagulant antigen, and higher ratio of factor VIII related antigen (EIA) to factor VIII activity (one-stage) and to factor VIII related antigen (RIA) respectively, than classified noncarriers. Individuals with blood group A, B, AB had significantly higher levels of factor VIII related antigen (EIA) and (RIA), and ristocetin cofactor, compared with blood group O. Obligate carriers with severe haemophilia A in their families had more bleeding symptoms than corresponding group with moderate haemophilia.

ABO Blood-Group System↗
PubMed1982

Carriers and noncarriers of haemophilia A. Evaluation of bleeding symptoms registered by a self-administered questionnaire with binary (no/yes) questions.

Carriers of haemophilia A were recently described to have significantly more bleeding symptoms than healthy females. Eighteen obligate carriers and 20 females classified as carriers with approximately 95% confidence, as described in an accompanying paper, were compared with 56 noncarriers with respect to ten bleeding symptoms, registered by a questionnaire. A rank-order of negative findings indicating noncarrier state is presented, as well as a rank order of positive findings indicating carrier state. A summation index of the total diagnostic capacity of the ten questions shows that carriers have more bleeding symptoms than healthy females.

Adolescent↗